Search Results (8,548)

Paper-based colorimetric biosensors represent a promising class of low-cost diagnostic tools that do not require external instrumentation. However, their broader applicability is limited by the environmental concerns associated with conventional metal-based nanomaterials and the subjectivity of visual interpretation. To address these challenges, this study introduces a proof-of-concept platform—using CA19-9 as a model biomarker—that integrates naturally derived melanin nanoparticles (MNPs) with machine learning-based image analysis to enable environmentally sustainable and analytically robust colorimetric quantification. Upon target binding, MNPs induce a concentration-dependent color transition from yellow to brown. This visual signal was quantified using a machine learning pipeline incorporating automated region segmentation and regression modeling. Sensor areas were segmented using three different algorithms, with the U-Net model achieving the highest accuracy (average IoU: 0.9025 ± 0.0392). Features extracted from segmented regions were used to train seven regression models, among which XGBoost performed best, yielding a Mean Absolute Percentage Error (MAPE) of 17%. Although reduced sensitivity was observed at higher analyte concentrations due to sensor saturation, the model showed strong predictive accuracy at lower concentrations, which are especially challenging for visual interpretation. This approach enables accurate, reproducible, and objective quantification of colorimetric signals, thereby offering a sustainable and scalable alternative for point-of-care diagnostic applications. Full article

Background/Objectives: Maxillofacial silicone prostheses’ long-term color stability remains a challenge. This study aimed to evaluate and compare the color stability of conventional and digital maxillofacial silicone elastomers mixed with nano-sized antimicrobial additives (ZnO nanoparticles and chlorhexidine salt-CHX) at various concentrations over a 10-week period. Methods: A total of nine groups (n = 10) of maxillofacial silicone elastomers were prepared. These included a control group (no additives), conventionally pigmented silicone, digitally pigmented silicone (Spectromatch system), and silicone mixed with ZnO or CHX at 1%, 3%, and 5% by weight. Specimens were fabricated in steel molds and cured at 100 °C for 1 h. Color measurements were performed at baseline and after 1, 4, 6, and 10 weeks using a Minolta Chroma Meter (CIELAB system, ΔE₀₀ formula). Data were analyzed using two-way ANOVA and Tukey HSD post hoc tests (α = 0.05). Results: Color changes (ΔE₀₀) ranged from 0.74 to 2.83 across all groups. The conventional pigmented silicone group showed the highest color difference (ΔE₀₀ = 2.83), while the lowest was observed in the ZnO 1% group (ΔE₀₀ = 0.74). Digital silicone and all antimicrobial-modified groups exhibited acceptable color stability (ΔE₀₀ < 3.1). Time significantly affected color difference, with the largest change occurring during the first four weeks (p < 0.05), followed by stabilization. Regression analysis confirmed high color stability over time for all groups except the conventional pigmented group. Conclusions: This is one of the first studies to directly compare digital and conventional pigmentation methods combined with nano-antimicrobials in maxillofacial silicones. Maxillofacial silicone elastomers mixed with up to 5% ZnO or CHX maintained acceptable color stability over 10 weeks. Digital pigmentation is similar to conventional methods. The incorporation of nano-antimicrobials offers significant microbial resistance and improved color retention. Full article

The present study focuses on the effect of doping KH560-modified cellulose nanocrystals (CNCs) on the electro-optical characteristics of polymer-dispersed liquid crystals (PDLCs). PDLC films were fabricated through the polymerization-initiated phase separation (PIPS) process and doped with CNC nanoparticles at various concentrations. At low concentrations, the CNCs at the interface, by virtue of their unique chiral characteristics, induce an orderly arrangement of liquid crystal molecules. Meanwhile, the interaction between the film’s fiber structure and the liquid crystal droplets brings about an augmentation in the arrangement efficiency. The excellent dispersion of CNCs diminishes the random alignment of liquid crystal molecules and mitigates light scattering. Additionally, it aids in the deflection of the liquid crystal director, facilitating the lubrication of the liquid crystals’ movement. It is remarkable that within the range of relatively lower CNCs doping concentrations, specifically from 0.005 wt% to 0.05 wt%, the PDLC films exhibit lower threshold and saturation voltages, faster response, enhanced viewing angle performance and higher contrast. Full article

Cobalt and Nickel (Co, Ni) co-doped magnesium oxide (MgO) nanoparticles (NPs) have been synthesized using the coprecipitation method. The structural, chemical, and optical properties of the as-synthesized NPs are systematically investigated using X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and UV-visible spectroscopy. It is found that the optical bandgap of co-doped MgO NPs reduces from 2.30 to 1.98 eV (14%) with increasing Ni dopant concentrations up to 7%. The Co_0.05Ni_0.07Mg_0.88O NPs exhibit a high photocatalytic degradation efficiency of 93% for methylene blue dye (MB) under natural sunlight irradiation for 240 min. Our findings indicate that the Co_0.05Ni_xMg_0.95−xO NPs have strong potential for use as photocatalysts in industrial wastewater treatment. Full article

Appropriate carriers or templates are crucial for maintaining the stability, biological activity, and bioavailability of selenium nanoparticles (SeNPs). Selecting suitable templates remains challenging for fully utilizing SeNPs functionalities and developing applicable products. Exosome-like nanoparticles (ELNs) have gained importance in drug delivery systems, yet research on selenium products prepared using exosomes remains limited. To address this gap, we utilized Cyperus bean ELNs to deliver SeNPs, investigated three preparation methods for SeNPs-ELNs, identified the optimal approach, and performed characterization studies. Notably, all three methods successfully loaded SeNPs. Ultrasonic cell fragmentation is the optimal approach, achieving significant increases in selenium loading (5.59 ± 0.167 ng/μg), enlargement of particle size (431.17 ± 10.78 nm), and reduced absolute zeta potential (−4.1 ± 0.43 mV). Moreover, both exosome formulations demonstrated enhanced stability against aggregation during storage at 4 °C, while their stability varied with pH conditions. In vitro digestibility tests showed greater stability of SeNP-ELNs in digestive fluids compared to ELNs alone. Additionally, neither ELNs nor SeNP-ELNs exhibited cytotoxicity toward LO₂ cells, and the relative erythrocyte hemolysis remained below 5% at protein concentrations of 2.5, 7.5, 15, 30, and 60 μg/mL. Overall, ultrasonic cell fragmentation effectively loaded plant-derived exosomes with nano-selenium at high capacity, presenting new opportunities for their use as functional components in food and pharmaceutical applications. Full article

Among the new strategies for managing diseases in agricultural crops is the application of metallic nanoparticles due to their ability to inhibit the development of phytopathogenic microorganisms and to induce plant defense responses. Therefore, this research evaluated the effects of silver (AgNPs), zinc oxide (ZnONPs), and silicon dioxide (SiO₂NPs) nanoparticles on symptom progression and physiological parameters in two pathosystems: Pseudomonas syringae pv. tomato (Psto) in tomato (pathosystem one, culturable pathogen) and Candidatus Liberibacter solanacearum (CaLso) in pepper plants (pathosystem two, non-culturable pathogen). For in vitro pathosystem one assays, SiO₂NPs did not inhibit Psto growth. The minimum inhibitory concentration (MIC) was 31.67 ppm for AgNPs and 194.3 ppm for ZnONPs. Furthermore, the minimum lethal concentration (MLC) for AgNPs was 100 ppm, while for ZnONPs, it was 1000 ppm. For in planta assays, ZnONPs, AgNPs, and SiO₂NPs reduced the number of lesions per leaf, but only ZnONPs significantly decreased the severity. Regarding pathosystem two, AgNPs, ZnONPs, and SiO₂NPs application delayed symptom progression. However, only AgNPs significantly reduced severity percentage. Moreover, treatments with AgNPs and SiO₂NPs increased the plant height and dry weight compared to the results for the control. Full article

Growing interest in the future applications of nanotechnology in medicine has led to groundbreaking developments in nanosensors. Nanosensors are excellent platforms that provide reliable solutions for continuous monitoring and real-time detection of clinical targets. Nanosensors have attracted great attention due to their remarkable sensitivity, portability, selectivity, and automated data acquisition. The exceptional nanoscale properties of nanomaterials used in the nanosensors boost their sensing potential even at minimal concentrations of analytes present in a clinical sample. Along with applications in diverse sectors, the beneficial aspects of nanosensors have been exploited in healthcare systems to utilize their applications in diagnosing, treating, and preventing diseases. Hence, in this review, we have presented an overview of the disease-prognostic applications of nanosensors in chronic diseases through a detailed literature analysis. We focused on the advances in various nanosensors in the field of major diseases such as cancer, cardiovascular diseases, diabetes mellitus, and neurodegenerative diseases along with other prevalent diseases. This review demonstrates various categories of nanosensors with different nanoparticle compositions and detection methods suitable for specific diagnostic applications in clinical settings. The chemical properties of different nanoparticles provide unique characteristics to each nanosensors for their specific applications. This will aid the detection of potential biomarkers or pathological conditions that correlate with the early detection of various diseases. The potential challenges and possible recommendations of the applications of nanosensors for disease diagnosis are also discussed. The consolidated information present in the review will help to better understand the disease-prognostic potentials of nanosensors, which can be utilized to explore new avenues in improved therapeutic interventions and treatment modalities. Full article

Polyvinyl chloride (PVC) is commonly employed as mulch in agriculture to boost crop yields. However, its toxicity is often overlooked. Due to its chemical stability, resistance to degradation, and the inadequacy of the recycling system, PVC tends to persist in farm environments, where it can decompose into microplastics (MPs) or nanoplastics (NPs). The radish (Raphanus sativus L.) was chosen as the model plant for this study to evaluate the underlying toxic mechanisms of PVC NPs on seedling growth through the integration of multi-omics approaches with oxidative stress evaluations. The results indicated that, compared with the control group, the shoot lengths in the 5 mg/L and 150 mg/L treatment groups decreased by 33.7% and 18.0%, respectively, and the root lengths decreased by 28.3% and 11.3%, respectively. However, there was no observable effect on seed germination rates. Except for the peroxidase (POD) activity in the 150 mg/L group, all antioxidant enzyme activities and malondialdehyde (MDA) levels were higher in the treated root tips than in the control group. Both transcriptome and metabolomic analysis profiles showed 2075 and 4635 differentially expressed genes (DEGs) in the high- and low-concentration groups, respectively, and 1961 metabolites under each treatment. PVC NPs predominantly influenced seedling growth by interfering with plant hormone signaling pathways and phenylpropanoid production. Notably, the reported toxicity was more evident at lower concentrations. This can be accounted for by the plant’s “growth-defense trade-off” strategy and the manner in which nanoparticles aggregate. By clarifying how PVC NPs coordinately regulate plant stress responses via hormone signaling and phenylpropanoid biosynthesis pathways, this research offers a scientific basis for assessing environmental concerns related to nanoplastics in agricultural systems. Full article

Nanofertilizers (NFs) and engineered nanoparticles (NPs) are increasingly used in agriculture, yet their environmental safety remains poorly understood. This study evaluated the comparative phytotoxicity of zinc oxide (ZnO), titanium dioxide (TiO₂), and clinoptilolite nanoparticles, three commercial nanofertilizers, and potassium dichromate (K₂Cr₂O₇) using Lactuca sativa seeds under adapted OECD-208 protocol conditions. Seeds were exposed to varying concentrations of each xenobiotic material (0.5–3% for NFs; 10–50% for NPs), with systematic assessment of seedling survival, root and hypocotyl length, dry biomass, germination index (GI), and median effective concentration (EC₅₀) values. Nanofertilizers demonstrated significantly greater phytotoxicity than engineered nanoparticles despite lower application concentrations. The toxicity ranking was established as NF1 > NF3 > NF2 > NM2 > NM1 > NM3, with NF1 being most toxic (EC₅₀ = 1.2%). Nanofertilizers caused 45–78% reductions in root length and 30–65% decreases in dry biomass compared with controls. GI values dropped to ≤70% in NF1 and NF3 treatments, indicating concentration-dependent growth inhibition. While nanofertilizers offer agricultural benefits, their elevated phytotoxicity compared with conventional nanoparticles necessitates rigorous pre-application safety assessment. These findings emphasize the critical need for standardized evaluation protocols incorporating both physiological and ecotoxicological endpoints to ensure safe xenobiotic nanomaterial deployment in agricultural systems. Full article

Ecotribology focuses on both saving energy resources and reducing environmental pollution. Considering environmental concerns, water-based nanolubricants have gained significant attention over conventional oil-based ones. Non-ecotoxic and highly environmentally friendly nanoadditives were chosen for nanolubricant synthesis, especially considering their use at elevated temperatures. In this study, hexagonal boron nitride nanosheets (hBNNSs) and titanium dioxide nanoparticles (TiO₂ NPs) were used to prepare water-based lubricants with glycerol and surfactant sodium dodecyl benzene sulfonate (SDBS) in water under ultrasonication. An Rtec ball-on-disk tribometer was used to investigate the tribological performance of the synthesised water-based lubricants containing different nano-hBN/TiO₂ concentrations, with dry and water conditions used as benchmarks. The results indicated that the water-based nanolubricant containing 0.5 wt% hBN and 0.5 wt% TiO₂ exhibited the best tribological performance at both ambient (25 °C) and elevated (500 °C) temperatures. This optimal concentration leads to a reduction in the coefficient of friction (COF) by 72.9% and 37.5%, wear of disk by 62.5% and 49%, and wear of ball by 74% and 69% at ambient and elevated temperatures, respectively, compared to that of distilled water. Lubrication mechanisms were attributed to the rolling, mending, tribofilm, solid layer formation, and synergistic effects of hBNNSs and TiO₂ NPs. Full article

The detection of trace chemicals at low and ultra-low concentrations is critical for applications in environmental monitoring, medical diagnostics, food safety and other fields. Conventional detection techniques often lack the required sensitivity, specificity, or cost-effectiveness, making real-time, in situ analysis challenging. Surface-enhanced Raman spectroscopy (SERS) is a powerful analytical tool, offering improved sensitivity through the enhancement of Raman scattering by plasmonic nanostructures. While noble metals such as Ag and Au are currently the reference choices for SERS substrates, fabrication methods should balance enhancement efficiency, reproducibility and scalability. In this study, we propose a novel approach for SERS substrate fabrication using reactive Aerosol Jet Printing (r-AJP) as an innovative additive manufacturing technique. The r-AJP process enables in-flight Ag seed reduction and nucleation of Ag nanoparticles (NPs) by mixing silver nitrate and ascorbic acid aerosols before deposition, as suggested by computational fluid dynamics (CFD) simulations. The resulting coatings were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses, revealing the formation of nanoporous crystalline Ag agglomerates partially covered by residual matter. The as-prepared SERS substrates exhibited remarkable SERS activity, demonstrating a high enhancement factor (10⁶) for rhodamine (R6G) detection. Our findings highlight the potential of r-AJP as a scalable and cost-effective fabrication strategy for next-generation SERS sensors, paving the way for the development of a new additive manufacturing tool for noble metal material deposition. Full article

This study evaluated the effects of liquid oregano oil, chitosan nanoparticles with encapsulated liquid oregano oil, and a negative control of empty chitosan nanoparticles on in vitro ruminal fermentation. Three Boer goats were used as ruminal fluid donors, fed with a formulated ration for 21 d for inoculum adaptation. Treatments tested on in vitro assays were diet without oregano oil or nanoparticles (CON); diet with 100 ppm of oregano oil in nanoparticles (100N); diet with 300 ppm of liquid oregano oil (300L); diet with 300 ppm of oregano oil in nanoparticles (300N); and diet with 300 ppm of empty nanoparticles (300CHN). The variables studied were in vitro dry matter digestibility (ivDMD), in vitro neutral detergent fiber digestibility (ivNDFD_om), total gas production (TGP), ammonia nitrogen concentration (NH₃), and pH. The experimental design was a randomized complete block design. Linear and quadratic regressions were used to identify dependence and inflection points. The ivDMD increased at 12, 36, and 48 h, with 300N and with 300L exhibiting increased ivNDFD_om at 36 h. Ruminal pH was highest (p < 0.05) with 300CHN at 36 h. For first-order regression analysis of TGP, coefficients (β) were highest (p < 0.05) for 300N. In conclusion, 300N increased ruminal fermentation in vitro, as reflected by increases in ivDMD, ivNDFD_om, and TGP. Full article

High-performance hydrogen gas sensors have gained considerable interest for their crucial function in reducing H₂ explosion risk. Although MoS₂ has good potential for chemical sensing, its application in hydrogen detection at room temperature is limited by slow response and incomplete recovery. In this work, Pd-doped MoS₂ thin films are deposited on a Si substrate, forming Pd-doped MoS₂/Si heterojunctions via magnetron co-sputtering. The incorporation of Pd nanoparticles significantly enhances the catalytic activity for hydrogen adsorption and facilitates more efficient electron transfer. Owing to its distinct structural characteristics and sharp interface properties, the fabricated Pd-doped MoS₂/Si heterojunction device exhibits excellent H₂ sensing performance under room temperature conditions. The gas sensor device achieves an impressive sensing response of ~6.4 × 10³% under 10,000 ppm H₂ concentration, representing a 110% improvement compared to pristine MoS₂. Furthermore, the fabricated heterojunction device demonstrates rapid response and recovery times (24.6/12.2 s), excellent repeatability, strong humidity resistance, and a ppb-level detection limit. These results demonstrate the promising application prospects of Pd-doped MoS₂/Si heterojunctions in the development of advanced gas sensing devices. Full article

The most prevalent growth of Candida cells is based on biofilm development, which causes the intensification of antifungal resistance against a large range of chemicals. Nanoparticles can be synthesized using green methods via various biological extracts and reducing agents to control Candida biofilms. This study aims to compare copper oxide nanoparticles (CuONPs) synthesized through chemical methods and those synthesized using Cinnamomum verum-based green methods against Candida infections and their biofilms isolated from Iraqi patients, with the potential to improve treatment outcomes. The physical and chemical properties of these nanoparticles were characterized using Fourier-transform infrared spectroscopy (FT-IR,) scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM) and X-ray diffraction (XRD). Four strains of Candida were isolated and characterized from Iraqi patients in Tikrit Hospital and selected based on their ability to form biofilm on polystyrene microplates. The activity of green-synthesized CuONPs using cinnamon extract was compared with both undoped and doped (Fe, Sn) chemically synthesized CuONPs. Four pathogenic Candida strains (Candida glabrata, Candida lusitaniae, Candida albicans, and Candida tropicalis) were isolated from Iraqi patients, demonstrating high biofilm formation capabilities. Chemically and green-synthesized CuONPs from Cinnamomum verum showed comparable significant antiplanktonic and antibiofilm activities against all strains. Doped CuONPs with iron or tin demonstrated lower minimum inhibitory concentration (MIC) values, indicating stronger antibacterial activity, but exhibited weaker anti-adhesive properties compared to other nanoparticles. The antiadhesive activity revealed that C. albicans strain seems to produce the most resistant biofilms while C. glabrata strain seems to be more resistant towards the doped CuONPs. Moreover, C. tropicalis was the most sensitive to all the CuONPs. Remarkably, at a concentration of 100 µg/mL, all CuONPs were effective in eradicating preformed biofilms by 47–66%. The findings suggest that CuONPs could be effective in controlling biofilm formation by Candida species resistant to treatment in healthcare settings. Full article

Current work investigates the fabrication and performance of nanocomposite membranes, modified with varying concentrations of hybrid nanostructures comprising titanium nanowires coated with iron nanoparticles (TiO₂ NWs-Fe₂O₃), for the removal of Naphthol Blue Black (NBB) dye from industrial wastewater. A series of analytical tools were employed to confirm the successful modification including scanning electron microscopy and EDX analysis, porosity and hydrophilicity measurements, Fourier-transform infrared spectroscopy, and X-Ray Diffraction. The incorporation of TiO₂ NWs-Fe₂O₃ has enhanced membrane performance significantly by increasing the PWF and improving dye retention rates of nanocomposite membranes. At 0.7 g of nanostructure content, the modified membrane (M8) achieved a PWF of 93 L/m²·h and NBB dye rejection of over 98%. The flux recovery ratio (FRR) analysis disclosed improved antifouling properties, with the M8 membrane demonstrating a 73.4% FRR. This study confirms the potential of TiO₂ NWs-Fe₂O₃-modified membranes in enhancing water treatment processes, offering a promising solution for industrial wastewater treatment. These outstanding results highlight the potential of the novel PES-TiO₂ NWs-Fe₂O₃ membranes for dye removal and present adequate guidance for the modification of membrane physical properties in the field of wastewater treatment. Full article